ALBANY, N.Y. - Rat poison was found in pet food blamed for the deaths of at
least 17 cats and dogs, but scientists said Friday they still don't know how
it got there and predicted more animal deaths would be linked to it. 

After the announcement, the company that produced the food expanded its recall
to include all 95 brands of the "cuts and gravy" style food, regardless of when
they were produced. The company also said it would take responsibility for pet
medical expenses incurred as a result of the food.  The substance in the food
was identified as aminopterin, a cancer drug that once was used to induce abortions
in the United States and is still used to kill rats in some other countries, state
Agriculture Commissioner Patrick Hooker said. The federal government prohibits using
aminopterin for killing rodents in the U.S. State officials would not speculate on
how the poison got into the pet food, but said no criminal investigations had been
launched. The pet deaths led to a recall of 60 million cans and pouches of dog and
cat food produced by Menu Foods and sold throughout North America under 95 brand
names. Some pets that ate the recalled brands suffered kidney failure, and the company
has confirmed the deaths of 15 cats and two dogs.

The latest death, a Yorkshire terrier named Pebbles, occurred Thursday. The dog
died of kidney failure after eating some of the food. Her owner, Jeff Kerner,
said he was contacting an attorney because he wanted to prevent another pet tragedy.
"Before they put this stuff in the bags, there should be some kind of test," said
Kerner, of Sherman Oaks, Calif. "I can't just let it go. Even if they just change
the law." The company expanded the recall — which initially covered only cans and
pouches of food packaged from Dec. 3 through March 6 — after the FDA alerted it that
some products remained on store shelves.

There is no risk to pet owners from handling the food, officials said.

The Food and Drug Administration has said the investigation into the pet deaths was
focused on wheat gluten in the food. The gluten itself would not cause kidney
failure, but it could have been contaminated, the FDA said. Bob Rosenberg, senior
vice president of government affairs for the National Pest Management Association,
said it would be unusual for the wheat to be tainted. "It would make no sense to spray
a crop itself with rodenticide," Rosenberg said, adding that grain shippers typically
put bait stations around the perimeter of their storage facilities.

Scientists at the New York State Animal Health Diagnostic Center at Cornell University
and at the New York State Food Laboratory tested three cat food samples provided by
the manufacturer and found aminopterin in two of them. The two labs are part of a
network created after the Sept. 11 terrorist attacks to keep the nation's animals
and food supply safe. "Any amount of this product is too much in food," Hooker said.
Aminopterin is highly toxic in high doses. It inhibits the growth of malignant cells
and suppresses the immune system. In dogs and cats, the amount of aminopterin
found — 40 parts per million — can cause kidney failure, according to Bruce Akey,
director of Cornell's diagnostic center. "It's there in substantial amounts," Akey said.
Donald Smith, dean of Cornell's veterinary school, said he expected the number of pet
deaths to increase. "Based on what we've heard the last couple days, 16 is a low number,"
Smith said. Aminopterin is no longer marketed as a cancer drug, but is still used in research,
said Andre Rosowsky, a chemist with the Dana Farber Cancer Institute in Boston. 
Rosowsky speculated that the substance would not show up in pet food "unless somebody
put it there."  Paul Henderson, chief executive of Ontario, Canada-based Menu Foods,
said the company does not believe the food was tampered with because the recalled food
came from two different plants, one in Kansas, one in New Jersey. Menu continues to produce
food at the two plants. The company, already facing lawsuits, said Friday it is testing all
the ingredients that go into the food.  "We have a lot of work to do, and we are eager to get
back to it," Henderson said. "This is a highly unusual substance."  When asked whether there
would compensation for medical bills for sick pets, Henderson said "to the extent that we
identify that the cause of any expenses incurred are related to the food, Menu will take
responsibility for that."  A complete list of the recalled products along with product codes,
descriptions and production dates was posted online by Menu Foods.  The company also designated
two phone numbers that pet owners could call for information: (866) 463-6738 and (866) 895-2708. 
___ 
Associated Press writers Andrew Bridges in Washington, Michael Virtanen in Albany and Solvej Schou
in Los Angeles contributed to this report"